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3 years ago

7x + 2y=24 8x + 2y=30

Mathematics

1 answer:

Bumek [7]3 years ago

3 0

Answer:

x=6 y=-9

Step-by-step explanation:

Layer the equations on each other as you would in a subtraction problem:

8x + 2y=30

7x + 2y=24

Subtract the equation just like you would normally. This should leave 1x=6 or x=6.
Now that you have your x value, plug it in as x for one of the equations. For the 2nd equation, this leaves:

42+2y=24 then

2y=-18 then

y=-9

Double check your y value by plugging x=6 into the first equation. This should also leave y=-9.

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Step-by-step explanation:

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Art [367]

Answer:

The answer is " $\bold{T = - 7.5 \cos \frac{\pi}{12}( t - 4 )+ 10.5}$ "

Step-by-step explanation:

Given value:

Temp-maximum= $18^{\circ}$

Temp. minimum = $3^{\circ}$

It is halfway between 10 am and 10 pm to 4 am.

The sinus and cosine roles could be used throughout the year to predict fluctuations in climate models. Its type of formula that can be used to model such information is:

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$B = \frac{2 \pi}{24}\\\\$

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D = 7.5 + 3 = 10.5

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$T = - 7.5 \cos \frac{\pi}{12}( t - 4 )+ 10.5$

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vitfil [10]

Hello,

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3 years ago

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Marizza181 [45]

Associative property of addition represents this equation:
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=> 48 + 82
=> Let's start with the ones place value.
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If we are going to do it vice versa, still expect that the same answer will occur.

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2 years ago